The problem is, the plebians would not be able to get a job to pay for the goods/services no matter how cheap they may become.

If you had robots making everything you could possibly want, why would you bother selling any of it to people who don't have any land, natural resources, or rare skills? They wouldn't have anything you want.

Why bother selling it at all? You could just give away the things for free. The marginal cost of an item is just the energy needed to produce it. With robots building solar panels or something like that, those costs are negligible.

Because it still takes effort to give things away for free and as a robot owner, natural resources, land, rare skills can't be automated away.

Effort is a human skill, which the premise states is already automated. As are rare skills.

If you can even automate giving things away without worrying about people hacking/stealing/vandalizing your robots, then wouldn't it also be likely for you to spend all your resources on combat robots to take resources/land from other robot owners instead of wasting them on people that aren't giving you anything you want?

Why would the elite worry about that, life is good in a monopoly, no need to upset the balance.

Because resources don't last forever? Nor are they distributed among the land equally (for example oil,rare earth elements, uranium).

Those are all current resources. The general currency is "energy" and "materials", and even materials are based on the energy in creating them (I don't think REEs are that rare, but they are hard to process).

There is no research to even suggest that we are going to be able to synthesize one type of matter to another arbitrary type without expending an absurd amount of energy, making it useless to do.

The idea that you could do something like that is even more outlandish than having robots that could automate everything a human could.

> one type of matter to another arbitrary type

But I didn't say this.

Certain materials can be substituted for another, but for high energy costs in making them.

Why would you give it away for free? Also, you're forgetting the cost of raw materials.

>If literally all imaginable human work was 100% automated then the cost of goods and services compared to today would be tiny

Well, that assumption is pretty general and doesn't account for natural resources/raw materials, energy inputs required for production, or other factors. It would also vary per sector, such that the statement is far from universally true.

>The poorest member of that society would live like a king from our present day world

But, regardless, there would be some cost for goods. How do you propose the now 100% unemployed population pay for anything, let alone "live like kings"?

The answer is that you would need to devise a method of wealth distribution that is orthogonal to capitalism. Say, for instance, a tax that subsidizes everyone else. That, of course, would not be capitalism.

The point is that wage labor is fundamental to capitalism. Somewhere between our present state and 100% automation, a capitalist system requires so much intervention that it breaks down.

I think taxing property ownership is the only natural conclusion i can draw from such an ultimate end-state. If you own any property, you pay a tax, and that tax is fed to those who do not own property, in such a way that they survive.

The cost would be low, but since nobody would have a job the prices would be astronomical. Multiply people's purchasing power by a million, great, but a million times zero is still zero.

>The poorest member of that society would live like a king from our present day world.

You forget things such as: meaningful work, respect from society, crime, cultural differences between the poor and the rich, interclass upward mobility (see any sociology textbook), intellectual stimulation.

No, capitalism would eat itself, you can't run an economy without consumers.

One could say it would hang itself by its own rope.